Re: select distinct runs slow on pg 10.6

On Tue, Sep 10, 2019 at 12:53 AM yash mehta <[email protected]> wrote:

> Hi Michael/Justin/Flo,
>
> Thank you all for your assistance. As Michael said, looks like there are
> no more tricks left.
>
> On Mon, Sep 9, 2019 at 9:09 PM Michael Lewis <[email protected]> wrote:
>
>> If you can't modify the query, then there is nothing more to be done to
>> optimize the execution afaik. Distinct is much slower than group by in
>> scenarios like this with many columns. You already identified the disk sort
>> and increased work mem to get it faster by 3x. There are not any other
>> tricks of which I am aware.
>>
>
Could you put a view in between the real table and the query that does the
group by ?  (since you can't change the query)
I'm wondering if the sort/processing time would be faster when that
distinct is invoked if the rows are already distinct.